“Even though the human race has been looking down at its underwear for centuries….” Shamelessly larding her narrative with puns and double entendres, Shaskan presents a general survey of unmentionables through the ages—arranged by function, from “Warmth” and “Protection” to “Making a Statement.” Illustrations are a mix of (understandably rare) period pictures and Dunnick’s comical, discreetly posed cartoon figures. Shaskan finishes off with speculations about undies of the future, plus a page of underwear-related historical incidents. This doesn’t match Deborah Nourse Lattimore’s pop-up I Wonder What’s Under There? (1998) for level of revelatory detail, but it’s certain to keep young readers in, so to speak, stitches. (Nonfiction. 7-10)